I was able to answer my own question through a lot of digging. I found a t-code that I was unaware of that will allow me to maintain the effective timeframe of the respective rates the t-code is AFAMSK. In that t-code, you set a Valid-To date in which the respective rate will be in effect until.

In my company, per regulation, it's required to change the respective depreciation rates every 5 years based on a depreciation study of the respective assets. These rates could potentially be different than the previous rates that have been set up in the prior years on the Multi-Level Method.

One option I can do is create all new Multi-Level Methods representing the new rates. I can then create all new depreciation keys and add in the intervals on all my respective assets. This could be quite voluminous.

Is there a way that I can add in the new rate in the respective MultiLevel Method so that beginning in the new fiscal year, all the respective assets will use the new rate?